CN-121673764-B - Preparation method of epoxy resin

Abstract

The invention discloses a preparation method of epoxy resin, which comprises the following steps of uniformly mixing a toughening agent and a curing agent to obtain a compound, wherein the curing agent is methyl hexahydrophthalic anhydride, the toughening agent is ZIF-8, preheating bisphenol A epoxy resin E51 for 15-20 min at 60-80 ℃ to obtain pretreated epoxy resin, mixing the pretreated epoxy resin with the compound at 60-80 ℃, adding a defoaming agent and an accelerator under the condition of stirring, reacting for 5-8 min at the constant temperature of 60-80 ℃ to obtain a mixture, and carrying out vacuum defoaming, curing and demolding on the mixture to obtain the epoxy resin. In the preparation method, the epoxy resin is toughened by utilizing the synergistic effect of the 2,4, 6-tris (dimethylaminomethyl) phenol and ZIF-8, and the prepared epoxy resin has good mechanical properties, and the impact strength of the epoxy resin can reach 28.24KJ/m 2 at most.

Inventors

• Qi Jianlei
• ZHANG YIXIANG
• WANG YANPING
• JI GUOJUN
• YANG PENGCHENG
• SU YANG

Assignees

• 内蒙古工业大学

Dates

Publication Date

20260505

Application Date

20260210

Claims (6)

1. 1. A preparation method of epoxy resin is characterized in that the epoxy resin is toughened by utilizing the synergistic effect of 2,4, 6-tris (dimethylaminomethyl) phenol and ZIF-8, and the preparation method comprises the following steps: Step 1, uniformly mixing a toughening agent and a curing agent to obtain a compound, wherein the ratio of the toughening agent to the curing agent is (0.08-0.12) 80, the curing agent is methyl hexahydrophthalic anhydride, and the toughening agent is ZIF-8; Step 2, preheating bisphenol A epoxy resin E51 at 60-80 ℃ for 15-20 min to obtain pretreated epoxy resin, mixing the pretreated epoxy resin with the compound at 60-80 ℃, adding an antifoaming agent and an accelerator under stirring, and reacting at the constant temperature of 60-80 ℃ for 5-8 min to obtain a mixture, wherein the ratio of the bisphenol A epoxy resin E51, the compound, the antifoaming agent and the accelerator is 100 (80-80.1): (0.8-1.2) in parts by weight, and the accelerator is 2,4, 6-tris (dimethylaminomethyl) phenol; And step 3, vacuum defoamating, solidifying and demoulding the mixture to obtain the epoxy resin.
2. 2. The preparation method according to claim 1, wherein in the step 1, the toughening agent is dried and then uniformly mixed with the curing agent, wherein the drying temperature is 110-120 ℃, and the drying time is 8-12 hours.
3. 3. The method according to claim 1, wherein in the step 2, the antifoaming agent is a polyether-modified polysiloxane-based oily antifoaming agent.
4. 4. The method according to claim 1, wherein in the step 2, the stirring speed is 8000 to 10000r/min.
5. 5. The method according to claim 1, wherein in the step 3, the vacuum degassing is performed at 60 to 80 ℃.
6. 6. The method according to claim 1, wherein in the step 3, the curing comprises maintaining at 110 to 120 ℃ for 3 to 4 hours, and naturally cooling to room temperature.

Description

Preparation method of epoxy resin Technical Field The invention belongs to the technical field of epoxy resin, and particularly relates to a preparation method of epoxy resin. Background Epoxy resins (EP) are high molecular weight polymers which form highly crosslinked physical structures during curing, and which have a wide range of applications in the matrix of advanced composite materials due to their outstanding mechanical strength, heat resistance and chemical stability. However, the high crosslinking density gives the epoxy resin excellent mechanical properties, and also limits the movement capability of molecular chains, so that the epoxy resin is easy to generate larger internal stress after curing, and further has obvious brittleness characteristics and poor impact resistance. Therefore, the research on the modification of epoxy resins has become a current key focus. Although the brittleness problem of the epoxy resin has become a key bottleneck for expanding the application of the epoxy resin, the conventional modification scheme still faces a plurality of challenges in practical application, and an ideal scheme for solving the problem of both performance and practicability has not been formed. At present, the epoxy resin has two main core challenges, namely, firstly, the contradiction that the toughening modification and the stability of the epoxy resin are difficult to reconcile exists, and secondly, the regulation and control process of a toughening system is complex and the effect is limited. The method is characterized in that the toughening material is added into the epoxy resin system, so that the thermal stability is poor, meanwhile, the toughening lifting range of the single toughening material on the epoxy resin is limited, multiple toughening agents of various types are required to be introduced into the multi-toughening system, complex interaction exists among the toughening agents of different types, the complex interaction mechanism is not completely disclosed, the synergistic toughening effect is difficult to fully develop, and the precise regulation and control of the epoxy resin are not facilitated. In addition, the nano-scale or micro-scale toughening agent is easy to generate agglomeration phenomenon in the epoxy resin matrix, and the toughening effect is greatly attenuated. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a preparation method of epoxy resin, wherein the epoxy resin is toughened by the cooperation of a toughening agent (ZIF-8) and a promoter. The aim of the invention is achieved by the following technical scheme. A preparation method of epoxy resin comprises the following steps: Step 1, uniformly mixing a toughening agent and a curing agent to obtain a compound, wherein the ratio of the toughening agent to the curing agent is (0.08-0.12) 80, the curing agent is methyl hexahydrophthalic anhydride (MeHHPA), and the toughening agent is ZIF-8; In the step 1, the toughening agent is dried first and then is uniformly mixed with the curing agent, wherein the drying temperature is 110-120 ℃, and the drying time is 8-12 hours. Step 2, preheating bisphenol A epoxy resin E51 at 60-80 ℃ for 15-20 min to obtain pretreated epoxy resin, mixing the pretreated epoxy resin with the compound at 60-80 ℃, adding an antifoaming agent and an accelerator under stirring, and reacting at the constant temperature of 60-80 ℃ for 5-8 min to obtain a mixture, wherein the ratio of the bisphenol A epoxy resin E51, the compound, the antifoaming agent and the accelerator is 100 (80-80.1): (0.8-1.2) in parts by weight, and the accelerator is 2,4, 6-tris (dimethylaminomethyl) phenol; In the step 2, the antifoaming agent is a polyether modified polysiloxane oil-based antifoaming agent. In the step2, the stirring speed is 8000-10000 r/min. And step 3, vacuum defoamating, solidifying and demoulding the mixture to obtain the epoxy resin. In the step 3, the vacuum defoaming is performed at 60-80 ℃. In the step 3, the solidification comprises the steps of keeping at 110-120 ℃ for 3-4 hours and naturally cooling to room temperature. Compared with the prior art, the invention has the following beneficial effects: 1. In the preparation method, the epoxy resin is toughened by utilizing the synergistic effect of the 2,4, 6-tris (dimethylaminomethyl) phenol and ZIF-8, and the prepared epoxy resin has good mechanical properties, and the impact strength of the epoxy resin can reach 28.24KJ/m 2 at most. 2. The invention adopts 2,4, 6-tri (dimethylaminomethyl) phenol as the accelerator, can accelerate the curing reaction, improves the crosslinking density, forms a more uniform epoxy network and balances the toughness. The alkalinity of the epoxy resin improves the dispersion uniformity of the toughening agent (ZIF-8) in the bisphenol A epoxy resin E51, effectively inhibits the occurrence of agglomeration, further optimizes interface bonding and improves the toughening